22 THE ENTOMOLOGIST. 
with scales, which make them appear rough. The mandibles are 
huge curved organs, serrate on the inner side at the tip. The 
maxille are three-jointed, lying forward between and below the 
mandibles ; the middle joint is the longest. The eyes are large, 
and there are no ocelli. The corneal facets are very prominent, 
so much so that the eyes look like a collection of ocelli rather 
than a single compound eye. ‘There is a bristle above and below 
each eye, and four others arranged in a quadrangle on the head. 
The labrum is shield-shaped with two long horns. The femora 
are short, the tibiz long, with rows of hair. The tarsi are one-- 
joimted, and provided with two hooks and a wineglass-shaped 
sucker. The prothorax is short and broad; the mesothorax has 
two papille bearing hairs; the metathorax and the six following 
segments are covered with similar hair-bearing papille, of which 
some, especially the lateral ones, are double. The abdomen then 
narrows, finally dilating at the tip. The animals fed on aphides 
of any kind, and eventually one ate up the other three in the box 
with him. They seize the aphides with their mandibles and suck 
them dry, then, lifting them on the end of the mandibles, place 
them on ther backs, where they are held by the long hairs. Often 
the aphis resists, trying to beat off the Chrysopa with its feet, 
but the fight is not of-long duration. Sometimes when there are 
no more aphides the Chrysopa places pieces of stick and other 
rubbish on its back. It is probable that the Chrysopa so covers 
itself to conceal itself from the aphides, among which it feeds. 
But it seems to me that the larva of Cassida, which similarly 
bears its excreta on its back, does so to mimic the Chrysopa larva 
rather than to conceal itself or shade itself, as has been suggested, 
from the sun. On September 2nd one changed its skin. When I 
saw it, it had firmly fixed itself by its tail to the glass of the box 
in which it was confined, and was nearly free. The limbs lay 
folded together, and were transparent ; it extricated itself from 
the skin by wriggling the body, standing almost upright on its 
tail. Previously to this all had been becoming darker ; now the 
one who had cast his skin was quite clear, but he very soon got 
darker, being spotted with dark grey on the belly and dark 
in colour on the back. Shortly after, this one ate up all the others 
who had grown much more slowly, and were not so far advanced. 
Now the mandibles are reddish yellow and transparent, darker at 
